Water-meter.



No. 65|,6|7. Patented lune I2, |900.

J. A. TILDEN.

WATER METER.

- (Application med July 15, 189e.)

(No Model.)

1| m.. .mm

l lh 'Illlll NITED STATES PATENT OFFICE.

JAMES A. TILDEN, OF IIYDE PARK, MASSACIIUSE"'1`S, ASSIGNOR 'IO 'lllll IIERSEY MANUFACTURING COMPANY, OF BOSTON, MASSACIUHET'IS.

WATER-Ni ETER.

SPECIFICATION forming' part of Letters Patent. No. 651,617, dated J une 12, 1900. v Application filed .Tuly 15,1898. Serial No. 685,986. A(No model) l rangement being such that no part of the me:

ter or meter-casing is injured or displaced by the freezing of the water, all of the working parts remaining in their normal relative positions at all times and resuming their normal operation after the ice has thawed. y

Various expediente have been adopted for thepurpose of preventing injury to the actual working parts of water-meters by freezing,the construction heretofore adopted,how

ever, depending upon the yielding or breaking of some part of the outer casing'or its fastenings which can be easily and inexpensively replaced; but in those constructions in which there is actual rupture of a part the meter though not permanently injured to any material extent is rendered temporarily inoperative, thus necessitating repairs, which, however inexpensive, are troublesome. The meter, moreover, is temporarily disabled, so that leakageand water damage will ensue if the meter is not duly attended to.

ln carrying out the present invention ta portion of the space within the rigid outercasing of the meter is occupied bya yielding indestructible elastic cushion, such as an airchamber having ay -flexible wall, so that as the' temperature falls and the fluid begins to exert pressure above the normal the said cushp ion yields to said increase in pressure, the.

whole body of the Water thus having a larger space to .occupy as it expands in approaching the freezingpoint, so that when freezing `finally occurs neither the inner-'casing of the meter and its contained parts nor the outer casing of the meter is injured. The cushion being elastic and having sucient resistance to counteract the normal pressure of the water will resume its normal condition as soon as the pressure is relieved by the thawing ot the ice, so that as soon asthe temperature rises the meter at once becomes operative without repairs and without renewal or rcpositioning of any of` the parts. Furthermore, as has already lbeen stated, the expansion is allo .ved to be distributed throughout the entire body by the gradual yielding of the cushion, there being substantially no positive restraint, as is the case where a member is adapted to be actually broken away, since it is impossible to make such a member so that it will yield to a slight increase of pressure without involving liability of breakage under usual working conditions. Furthermore, in a construction in which the cuter casing is provided with a plug secured by screwthreads arranged to be stripped when a ccrtain predetermined pressure is encountered it is obvious that the screw-threads will exert resistance up to a certain point and will finally yield upon thesudden increase of pressure at the time when the water actually freezes, so that there is liability that the water contained within the inner casing instead of having its expansion distributed throughout the mass at the moment of solidifying may have the portion within the inner casing expand suddenly in the act of solidifying owing to the sudden relief of the pressure due to the rupture of the confining-walls, and thus strain the inner casing and injure the working parts even though the casing itself is saved by the yielding of the plug when the. threads are stripped.' An attempthas been made to overcome this objection by having a portion of lthe casing secured by yielding and resi-liis made by providing a iiexible resilient wall meter (which in such construction are loosely connected and inseparable, being normallyl retained in working position by the movable part of the casing when closed or in normal position) will not be restored to normal working position by the resilient fastenings whenv the ice is thawed. v

All of the above-named objections are ob-V viated by thepresent invention, which consists, broadly, in providing capacity for expansion of thefcontents of the meter or chamber to be protected from damage by'freczing without moyement of any of the working parts or of any part of the rigid casing or its fastenings. 4

In the preferable construction provision for expansion of the liquid contents of the meter exposed to the. pressure of the water in the casing, which wall normally withstands the pressure of the liquid when under normal conditions, but which yields when subjected to abnormal pressure, and lthus' affords in creased capacity for vthe Vliquid contents of ,the meter suicient to provide for the expansion of the liquid in solidfyingwhen thenormal inlet and outlet of the meter are closed or obstructed, as by the freezing ot the Water therein before the-water in -the meter itself isfrozen.

Figure 1 is a longitudinal section ot'l alwatermeter having provision for protection from injury by freezing embodyingr this invention; and Fig. 2 is a similar view showing amoditied construction, the dotted lines in 'each view showing the position ot the parts when the Water is'frozen or the pressure otherwise rendered' abnormal.

:I he meter, including the outer chamber or casing a, havinff'the' usual inlet and outlet passage b and c and the measuring appliances contained in the internal chamber (1,. may all be of usual construction, thel said v measuring-mechanism 'chamber having its parts permanently assembled and' without provision for separability or movement from the relative position which they occupy in the normal operation.

In order to protect the-outer chamber or casing a from bursting'and the working parts from damage by the enormous expansive pres- 'sure exerted by the liquid contents in case of freezing, the meter is in accordance with 'this inven tion provided with a iiexible walled chamber e, shown in Fig. 1 as a hollow sphere,

which maybe made of iexible india-rubber or other iexible material impervious to water and affording su icient'resistance to' compression to retain its normal expanded or spher 'chamber e.

ical shape when subjected onlytothe normal pressure of the liquid contained in or'liowing through-the meter. In case, however, the said liquid should forcibly expand while confined in the meter-chamber with the inlet and. outlet passage b anda obstructed, as takes pl/ace in case of -freezing, the abnormal pressure will com press and collapse the air-chambere, as shown in dotted'lines, thus afEording more space in the chamber a, for the liquid, which is thus permitted to expand with- 'out' increasing the internal pressure or strain upon the walls of the casing beyond the amount which is required to collapse the The liquid in this manner is permitted to expand without excessive increase in pressure to the point at'which it actuallyv solidiies, and there is therefore no sudden iow or change of position of the liquid at the instant 4of solidifying, and consequently no need of provision for separability of the parts of the measuring mechanism proper in the chamber d to prevent damage thereto when the liquid freezes. There is therefore a great advantage over that class of appliances in which there is no yielding or rupture until after the pressure of the expanding liquid has greatly exceeded the normal pressure, so that when the restraint to the liquid is finally overcome it is converted, substantially, instantaneously from the liquid to the solid condition, the change being accompanied by a sudden expansion throughout all its parts, which would rupture 4the internal chamber d or the measuring appliances proper unless provision were made' for separability of-its parts under such sudden expansive pressure-exerted therein. v

The invention is not limited to any specific IOO -form of the yielding wall within the rigid :o5

parts of the casing, and, as shown in Fig. 2,

a somewhat different form of internal yielding wall or collapsible chamber is provided. l As shown in Fig. 1, thewall of the vcharnber e has but little rigidity of i'tsown, and no therefore has to be normally retained in an expanded condition by air or similar elastic fluid contents, which should be under a`pressure about equal to the normal external pressure of the liquid in the meter, so as to retain x 15 the chamber properly expanded until the internal pressure is overcome by the increasing pressure of the external liquid due to its ex pansion in freezing."

As shown in Fig. walled chamber eis approximately cylindrical in shape and has its wall of sucient rigidity to sustain the normal external pressure without collapse, but suiiiciently flexible and elastic to yield under the abnormal pressure developed when the liquid freezes. l' f In either construction the capacity of the chamber e should be greater than the amount thatthe liquid contents of the meter inc in volume in freezing, so that the air eon- :3e

2, the internal 'flexible m.

tained in the chamber while being highly the pressure of the surrounding liquid, sub- *ro compressed when freezing takes place will stantially as and forthe purpose described.

still nobe compressed enoughtoexertapres- In testimony whereof I have sign d my sure sufficient. to endanger the breakage of name to this specification in the presence of 5 the main case @of the meter. two 'subscribing witnesses. y

.I elaim- JAMES A. TILDEN. Thecombinabion with the rigid outer cas- Witnesses: s ing of a. water-meter, of a exible walled air- H. J. LIVERMORE,

chamber contained therein and subjected to I NANCY P. FORD. 

